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Mare Nubium

[mahr-ey noo-bee-uh m, nyoo-, mair-ee]
noun
  1. (Sea of Clouds) a dark plain in the third quadrant of the face of the moon: about 95,000 sq. mi. (245,000 sq. km).
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018